Vitamin D, also known as the “sunshine” vitamin, increases bone strength, lowers blood pressure and reduces the risk of heart attacks, diabetes, rheumatoid arthritis and multiple sclerosis. Naturally occurring in the the sunlight that directly hits human skin, vitamin D is cheap to come by and in places like Florida, readily available.

But it is one of the most lacking nutrients amount humans worldwide. A 2012 study found that vitamin D insufficiency affects nearly half of the world’s population, with 1 billion people qualifying as having a deficiency. The shortfalls in vitamin D stretch across all age groups and ethnicities.

Even areas with the highest levels of sunlight year-round, like Florida, count vitamin D as a deficiency in many people.

Dr. George Guthrie works in family practice at the Centre for Family Medicine in Winter Park, and he echoes the research that Vitamin D is lacking in patients.

“Vitamin D isn’t a vitamin like we think of other vitamins. It’s a hormone. The main way we receive it is from the sun directly hitting our skin,” he said.

While Floridians have ample opportunities to seek sunlight, Guthrie says most of them spend the majority of their daylight hours inside. When people are outside, sunblock, protective clothing and hats block the sun.

“We don’t want people to burn in the sun because we know that increases risk for skin cancer. But we do need a little sun exposure to get our dose of vitamin D,” he said.

As far as official sun exposure recommendations for the sake of vitamin D, expert opinions vary.

The exact amount of sun and on how much skin depends on the person, and more specifically, on his or her skin tone. The darker the skin, the more sun exposure is needed, Guthrie said.

Age plays a role, too. The older a person, the more sun exposure is needed to reach vitamin D levels. A study on the effects of sunlight and UV rays from Polytechnic University of Valencia in Spain found that middle-aged adults have only 66 percent of the vitamin D-production potential of children and as people get even older, absorption of vitamin D gets even harder.

That study found that up to two hours of direct sun exposure a day is necessary in winter to absorb enough vitamin D, while just 30 minutes or less is needed in summer months. The researchers said part of this has to do with clothing covering more skin in the winter -- but the sun’s intensity also comes into play.

The American Academy of Dermatology recommends no sun exposure, citing the cancer risks of direct sunlight on skin. The AAD recommends a comprehensive sun protection plan that includes wearing sunscreen with an SPF of 30 or higher outside at all times.

Research from the University of Florida recommends 10 to 15 minutes of sunshine three times a week to meet vitamin D requirements. For optimal absorption, the sun needs to directly hit the skin on the face, arms, back or legs without sunscreen blocking the rays.

But if you’re not getting enough sun exposure, the right foods can help boost vitamin D levels and so can supplements.

“As a rule, I prescribe food. But in some cases a supplement is needed until levels are where they should be and sometimes it is needed permanently,” Guthrie said.

Megan Ware is a registered dietitian and the owner of Nutrition Awareness in Orlando who also takes a food-first, supplements second approach to client health. She says that the biggest nutrient deficiency she sees is vitamin D, followed by potassium.

There are so many people who lack proper amounts of both that the U.S. Food and Drug Administration will soon require amounts to be listed on nutrition labels.

“Vitamin C will soon be taken off as a label requirement because it’s no longer a nutrient of concern. I’ve never had one client that was vitamin C deficient,” Ware said.

Some of the best foods for addressing deficiencies in vitamin D, along with other essential nutrients, include kale, collard greens, beets, avocados and broccoli.

“Take a week and really look at each meal in front of you. How many veggies or fruits, emphasis on the veggies, are you getting in a day?” Ware said.

She says that supplements are exactly that -- meant to be used alongside a balanced diet.

“I have one motto that is relevant across the board for every client that walks through my door and it’s ‘food first.’ There’s no point in talking about vitamins and supplements if there isn’t a good base,” Ware said.

Kim McLeod Lett is a registered dietitian and nutritionist who also sees clients with vitamin D deficiency.

“You wouldn’t think people living in sunny Florida could be deficient in the sunshine vitamin,” Lett said.

Sweeping generalizations about vitamin deficiencies don’t help individuals, however. Only lab work can confirm exact deficiencies and help practitioners and patients determine the best course of action.

Sun exposure that is appropriate based on skin tone, time of year and age is the first step to obtaining enough vitamin D. Adding in vitamin D-rich foods can also help. Ware and Lett suggest the following foods for incorporation in a vitamin D-friendly diet:

Fatty fish like salmon, tuna, sardines, mackerel, and cod liver oil

Raw maitake mushrooms

Fortified skim milk

Fortified orange juice

Chicken eggs

“I personally take a whole-foods based multivitamin daily to cover my bases. Think of it as an insurance policy,” Ware said.

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